DESCRIPTION: This core will provide a centralized facility for assaying cytogenetic abnormalities and gene mutations, focused on the analysis of rodent model systems as a function of age. The Core is comprised of four major components: (i) It will provide measurements of cytogenetic integrity and DNA mutations and will additionally offer advice concerning aspects of genome instability such as monitoring of DNA damage, analysis of microsatellite instability, and methylation patterns. (ii) The Core contains a training component aimed at providing the users with advice in selecting the best assays for the model system being investigated and, most importantly, in interpreting results. (iii) As a general educational component, workshops will be organized to inform the San Antonio aging research community about progress in genomic instability and aging and to inform the group about new and emerging technologies. (iv) Effort will be devoted to continue the development and optimization of currently used assays for analysis of cytogenetic and mutational endpoints in aging.